Today, for the purpose of storing programs and data used by a computer with high reliability, a tape library device and a disk library device are utilized. In general, a library device comprises a member referred to as a magazine, which contains a plurality of cartridges (recording media, each of which is, in the case of a tape library device, one with a magnetic tape integrated with a reel), and a conveying device referred to as an accessor.
The magazine is partitioned into a plurality of cells inside, and each of the cells is configured to be able to contain one magazine. The accessor performs operation of extracting a cartridge contained in an arbitrary cell of an arbitrary magazine and setting it to a drive device, and operation of storing a cartridge extracted from the drive device into an arbitrary cell of an arbitrary magazine.
In such a library device, in the case of exchanging or charging a cartridge of only part of cells in a magazine, it is possible to extract a cartridge from such a cell or to charge a new cartridge to the cell by drawing out the magazine to the position of the cell. On the other hand, the device is configured also such that a magazine can be wholly drawn out from the device, and it is thus possible to take a magazine itself out of the device or to charge another magazine into the device.
In terms of such drawing of a magazine from a library device, for example, Patent Document 1 discloses a library device which makes it possible to release (draw) a tray in a stepwise manner by setting a mode of wholly releasing a tray and a mail slot mode of releasing a tray halfway.
Further, Patent Document 2 discloses a library device comprising a magazine holding structure which can change the draw amount of a magazine in a stepwise manner with a a simple mechanism with a reduced number of constituent parts. In the library device, a magazine has a rail comprising a plurality of steps in its bottom surface, and the main body of the device has a locking lever which is rotatable within the same plane as that of the bottom surface of the magazine, a spring which biases the locking lever in the direction of the magazine, and an accessor which can move past the side of the magazine in the direction of insertion and drawing. The engagement between the locking lever and the step is released with respect to each of steps by the rotation of the lock lever in the direction opposite to that of the spring's biasing. Thereby stepwise drawing of a magazine is made possible.